Enhancements in data storage have enabled massive amounts of information to be collected, stored, and analyzed. For example, many search engines retain information regarding what search terms have been used, identities of websites visited by users, what time of day, day of week, and the like web sites have been visited by users, amongst other data. Furthermore, collected data is not limited to data collected from computers and the Internet. In the modern world, more and more sensors are being used by consumers, wherein such sensors can determine, for instance, a location of a user, a current temperature of a user, temperature experienced by a user (e.g., eighty degrees), direction of movement of a user, velocity, acceleration, and/or deceleration of a user, amongst other information.
Information collected from multiple sensors including those that may be privately held may then be pooled and used by applications whose outputs are context-dependent. Pursuant to a particular example, applications exist that provide users with driving directions (e.g., a route) between two or more points, wherein the route may depend on current sensed conditions with respect to flows within a traffic system, based on such data as sensed congestion, sensed weather conditions, sensed current events (e.g., accidents), and other data. In many of these traffic-related applications, data is retrieved from sensors placed proximate to roadways, wherein the sensors are relatively expensive to install and maintain.
While consumer-level sensors are becoming more common (e.g., in smart phones, navigation equipment, etc.), users may often be hesitant to share data from the sensors due to concerns regarding privacy, power consumption, annoyance, etc. For instance, with respect to an application that desirably monitors location and/or velocity of a user, if the user is monitored over time, data from the sensor may be analyzed to determine where the user lives, where the user works, where the user travels, favourite shopping malls, and other information that many users deem as private. Taken a step further, this information may be used to determine the user's identity as well as their home address, typical travel routes, etc. Fears about sharing such data include the concerns about being tracked and being the recipient of unwanted targeted marketing by commercial entities.
One method for reducing privacy concerns of a user may be to request authorization from the user each time data pertaining to the user (e.g., from a sensor that corresponds to the user) is desired by the application. These types of requests, however, may interrupt the user when they wish not to be interrupted (e.g., while driving). Furthermore, users may not wish to donate battery and networking resources, such as the cost of communicating with a wireless service, required for sensing and transmitting data.